The following paragraphs are not an admission that anything discussed in them is prior art or part of the knowledge of persons skilled in the art.
U.S. Pat. No. 4,647,358 describes a current-feeding cathode-mounting device comprising a metal-sheathed carrying rail of copper and a permanent cathode plate consisting of the same material as the sheath and joined by welding at least along part of a longitudinal edge and wherein at least an end portion of the rail is unsheathed at least along part of its extent.
U.S. Pat. No. 7,332,064 describes a hanger bar for a cathode plate and a method of producing a cathode for electrolytic recovery of metal. The hanger bar comprises a support element which is preferably stainless steel and hollow. An electrically conductive metal cladding is affixed the stainless steel bar by any appropriate mechanism, e.g., interference fit, welding, chemical or mechanical fastening or coextrusion or roll forming.
U.S. Pat. No. 7,344,624 describes a cathode plate and method for electro-refining or electro-winning of metal. The cathode includes a cathode blade and hanger bar. A quantity of electrically conductive material is wrapped around the hanger bar and along the cathode blade to a position, in use, proximate the level of electrolyte in the electrolytic bath.